First‐principles study of the structural stability and electronic structures of TaN

Using the plane‐wave pseudopotential method within the generalized gradient approximation, we have studied the structural stability and electronic structures for several TaN phases. Our results show CoSn is the calculated ground‐state structure of TaN among the five crystallographic structures that have been studied. The order of energetic stability of phase structures of TaN from low to high is: CsCl < ZnS‐B3 < NaCl < WC < CoSn. The higher stability of TaN in the CoSn and WC structures is due to the formation of pseudogap around the Fermi level and the stronger hybridization between N‐2p states and Ta‐5d states. TaN in all structures studied has a metallic nature. The calculated bulk modulus indicates that TaN in the WC structure may be a less compressible material. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)